Geochemical Characteristics And Evaluation Of Soil Heavy Metals In Lecong, Shunde

Accompanied with the development of global urbanization, varieties of humanactivities such as urban industries and transportation have strongly affected the content ofheavy metals in soil. This paper carried out general exploration of ecological geochemistry(1:50000) in an120km2area, which include north and south sides of Shunde river “S”bend---a branch of Beijiang river in Guangdong province. This paper analyzes the contentof heavy metal elements in soil and discusses their spatial distribution characteristicsaccording to the different land use function. At the same time, it uses the correlationanalysis and factor analysis to analyze the sources of heavy metals in soil and utilizessingle gene index method and Nemerow multi-factor index method to evaluate theactuality of the soil pollution in study area. We got the following conclusion:The concentration of Hg, Cd, Ni, As, Pb and Zn in soil of studying area has highdegree of discreteness. Compared with soil background values of Guangdong province, thecontent of heave metals in study area soil reveals commonly enrichment. Sources of soilheavy metal are complexity with diverse matrix and causes. Shunde River has great effecton the content of Cd, Cu, Pb and Zn. Meanwhile the furniture factories and electricfactories affect the mass of heave metals in soil.The analysis of the spatial distribution characteristics of heavy metals in study soilreveals that three high-value anomaly regions of heavy metals exist there. Firstly, it isJinpinggang and its surrounding in the mid-west of the study area where seven kinds ofheavy metals have different high-value anomaly. Secondly, Leliu town in the southeast ofthe tudy area, which Zn, Ni, Cu and Cd have high-value anomaly. Thirdly, Shunde river“S” bend in the east of the study area in which Cd, As and Pb have high-value anomaly.Correlation analysis and factor analysis are contributed to analyze the sources ofheavy metals in soil, which figure out the following conclusions. First of all, there is aweak correlationship among whole heavy metals in the soil. However, Zn, Cu and Pb, Asboth have obvious correlation, which may indicater consistent source. Complex controlfactors mingled with varities of roles influence the source of heavy metal in study area.Second, factor analysis results show that4factors control the source of heave metals instudy area soil. Cd, Cu and Zn are controlled by factors of river and industrial. Pb and Asare controlled by factors of the traffic and industrial. Ni is affected by industrial pollution.Hg is affected by human factors. The pollution evaluation of heavy metals indicates the contamination in soil is veryserious with large area. Single gene index method shows the pollution of Cd has mostserious pollution, while the state of Pb and Ni is better than other heavy metals. In differentfunction areas, pollution has different type and degree. Nemerow multi-factor indexmethod shows the study area soil have suffered from different level of pollution. Soil in thecoast of Shunde River and the southwest of the study area has caused middle-high levelpollution. Besides, several micro-regions as islet in the northwest and northeast of thestudy area have the same pollution status. While, at present fishpond land has lighter levelheavy metals pollution.